05/20/2016 Crawler crane LR 11350 erects large near-shore wind farm on the Ijsselmeer

The massive crane required the help of a small ship's crane to pick up the rotor and turn it vertical.

The massive crane required the help of a small ship's crane to pick up the rotor and turn it vertical.

For around one year the IJsselmeer (Lake IJssel) in the north of the Netherlands was the scene of an unusual job for a LR 11350. The crawler crane erected the complete "Westermeerwind" wind farm from a massive jack-up platform. Crane contractor Mammoet completed the last of the 48 Siemens wind turbines with a hub height of 95 metres on schedule in February.

During the initial phase of the project from March 2015, gigantic foundation piles with a diameter of five metres had to be driven 25 metres into the bed of the lake. The monopiles measured up to 40 metres in length and weighed 300 tonnes. The Liebherr crawler crane position these massive tubes precisely using a radius of 36 metres.

All the foundation piles had been inserted by the end of May. After the technical equipment had been installed in the foundations and the turbines connected to the network during the months of summer, work was started in September on installing the tower segments, gondolas and rotor stars, the final phase of the project.

Large transport pontoons, each laden with the two-piece turbine tower and a gondola, were moved by tugs from the Port of Amsterdam to the construction site 60 kilometres away. The two tower sections measuring 50 and 40 metres in height were transported upright which enabled the LR 11350 to hoist and assemble the components without an auxiliary crane. The lower tower segment was the largest load for the crawler crane, weighing in at 150 tonnes. However the support of a small floating crane was required for lifting and tipping the rotor star. The rotors have a diameter of 108 metres and were assembled on the opposite coast of the IJsselmeer and then transported to the site on Arches.